This invention relates generally to the art of carding fibers and particularly to card clothing for the carding elements used with conventional carding machines.
The art of fiber carding is highly developed and the techniques employed therein well known. A conventional carding machine may consist of a rotating carding cylinder and a plurality of flat bars, commonly called flats, which surround about one-third of the surface of the carding cylinder. The surfaces of the carding cylinder and the flats are usually toothed or provided with upstanding wires, pins or needles so that the interaction of the carding cylinder and the flats opens and combs the fibers, removing foreign matter therefrom. The result of the carding process is a clean, combed, uniformly dispersed sheet or web. There are other types of cards and garnets that employ or use workers and strippers instead of flats to perform the carding of the fibers.
The carding cylinder rotates, and typically the flats move also, in the same direction as the carding cylinder, but at quite different speeds. In this known environment, these carding cylinder and flats provide the carding elements.
Typically, both the carding cylinder and the carding flat comprise a base or support upon which card clothing is mounted. Carding cylinders have been covered with wrappings of toothed metallic wire wound helically around the cylinder, this wire providing radially projecting teeth forming the card clothing on the cylinder. It has been known to construct flats by covering the supporting element with short strips of rigid metallic wire oriented parallel to the direction of fiber flow across the carding surface, this wire having outwardly projecting teeth like the toothed metallic wire wound helically around a supporting carding cylinder.
The metallic wire card clothing used in conventional carding operations and placed upon conventional carding elements such as cylinders, lickerins, doffers, flats, workers, strippers, and the like, has teeth provided on the toothed metallic wire forming the carding surface on the supporting element. Commonly, these teeth are provided in a saw-toothed configuration. Where the teeth are provided by a toothed metallic wire would helically around a cylinder, the outwardly extending height of the teeth on the wire convolutions has usually provided a uniform height to the card clothing. However, the prior art has suggested card clothing wherein the teeth in one convolution on the carding cylinder are of one uniform height whereas the teeth on the adjacent convolution of the carding cylinder are of a different uniform height.
In the prior art, carding fibers has aimed at forming a clean combed uniformly dispersed sheet or web of the fibers. In this regard the formation and orientation of the teeth providing the card clothing on a carding machine element has generally been characterized by having uniformity or at least similarity between the multitude of teeth defining a card clothing area on the carding element. While not overlooking the advantages of the heretofor known and utilized techniques espoused in the prior art, it has been found that in certain circumstances there are advantages to be obtained by providing a particular orientation and sizing of the teeth forming the card clothing surface. In this regard, the prior art concepts and apparatuses for providing carding surfaces are not found to function with the desired perfection in all carding applications.
Indeed it has been found that the ideal achievement of perfect combing of the fibers to give a uniformly dispersed web coming from the carding operation is not always the desired result of the carding operation. In this regard, a disorienting and tangling of the fibers making up the web being carded can provide a uniformly disoriented web fiber content with consequent increase in the cross-directional strength of the web that is produced.